Apparatus for fabricating an elastic nonwoven material

ABSTRACT

An apparatus for fabricating an elastic nonwoven material generally includes a rotary ultrasonic horn and a rotary anvil positionable in close proximity to the ultrasonic horn. The anvil has a face with a width and a circumferential axis. The face has a plurality of ridges each of which defines a plurality of interspaced lands and notches.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/141,496 filed on Apr. 1, 2015, U.S. Provisional Application No.62/235,880 filed on Oct. 1, 2015, and U.S. Provisional Application No.62/247,056 filed on Oct. 27, 2015, all of which are incorporated byreference herein in their entirety.

BACKGROUND

The present invention relates generally to elastic materials and, moreparticularly, to an apparatus for fabricating an elastic nonwovenmaterial.

Elastic nonwoven materials are utilized in a variety of articlesincluding personal care articles (e.g., adult briefs, baby diapers,child/adult pull-on pants, contour fit hygiene products, etc.) andmedical garments (e.g., masks, caps, gowns, footwear, etc.).

At least some conventional methods for fabricating elastic nonwovenmaterials include adhesively bonding elastic strands between layers ofnonwoven fabric when the elastic strands are in tension. Once theelastic strands are permitted to contract, the elastic strands gatherareas of the nonwoven fabric such that the nonwoven fabric functionswith an elastic property. However, the durability of elastic nonwovenmaterials made by these conventional methods is less than desirablebecause the adhesive bonds are prone to creep, which can result in aloss of elasticity over time. Moreover, it can be overly expensive tofabricate elastic nonwoven materials using these conventional methods.It would be useful, therefore, to provide a system for fabricating amore durable elastic nonwoven material in a more cost effective manner.

SUMMARY

In one embodiment, an apparatus for fabricating an elastic nonwovenmaterial generally comprises a rotary ultrasonic horn and a rotary anvilpositionable in close proximity to the ultrasonic horn. The anvil has aface with a width and a circumferential axis. The face has a pluralityof ridges each of which defines a plurality of interspaced lands andnotches.

In another embodiment, an apparatus for fabricating an elastic nonwovenmaterial generally comprises a horn module including a rotary ultrasonichorn mounted to a frame, and an anvil module including a rotary anvilmounted to a frame and positionable in close proximity to the ultrasonichorn. The apparatus also includes a camming device displaceablyconnecting the horn module and the anvil module to cyclically displacethe horn module relative to the anvil module during a bonding operationof the apparatus.

In yet another embodiment, an apparatus for fabricating an elasticnonwoven material generally comprises a horn module including a rotaryultrasonic horn mounted to a frame, and an anvil module including arotary anvil mounted to a frame and positionable in close proximity tothe ultrasonic horn. The apparatus also includes a pinching devicemounted to one of the frame of the horn module and the frame of theanvil module such that the pinching device is positionable to floatinglycontact the anvil.

BRIEF DESCRIPTION

FIG. 1 is a schematic illustration of a system for fabricating anelastic nonwoven material;

FIG. 2 is a perspective view of one embodiment of a rotary ultrasonicbonding apparatus for use in the system of FIG. 1;

FIG. 3 is a perspective view of another embodiment of a rotaryultrasonic bonding apparatus for use in the system of FIG. 1;

FIG. 4 is a partial cross-section of the apparatus of FIG. 3;

FIG. 5 is a perspective view of another embodiment of a rotaryultrasonic bonding apparatus for use in the system of FIG. 1;

FIG. 6 is an enlarged side elevation view of a pinching device of theapparatus of FIG. 5;

FIG. 7 is a perspective view of yet another embodiment of a rotaryultrasonic bonding apparatus for use in the system of FIG. 1;

FIG. 8 is a laid-flat illustration of an annular face of one embodimentof an anvil for use in the apparatuses of FIGS. 2-7;

FIG. 9 is a cross-section, taken along plane 9-9 of FIG. 8, of oneembodiment of a ridge defined by the anvil face of FIG. 8;

FIG. 10 is a cross-section, taken along plane 10-10 of FIG. 8, ofanother embodiment of a ridge defined by the anvil face of FIG. 8;

FIG. 11 is a cross-section, taken along plane 11-11 of FIG. 8, of yetanother embodiment of a ridge defined by the anvil face of FIG. 8;

FIG. 12 is a laid-flat illustration of a portion of an annular face ofanother embodiment of an anvil for use in the apparatuses of FIGS. 2-7;

FIG. 13 is a perspective view of the portion of the annular face of FIG.12;

FIG. 14 is an enlarged segment of the perspective view of FIG. 13 takenwithin area 14 of FIG. 13; and

FIG. 15 is a schematic illustration of an elastic nonwoven materialfabricated using an embodiment of the system of FIG. 1.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DETAILED DESCRIPTION

Referring to the drawings, and in particular to FIG. 1, a system forfabricating an elastic nonwoven material is indicated generally by 100.The illustrated system 100 includes a supply station indicated generallyby 102, a processing station indicated generally by 104, and acollection station indicated generally by 106. Other suitable stationsare also contemplated without departing from the scope of thisinvention.

In the illustrated embodiment, the supply station 102 includes aplurality of supply rolls each containing a non-woven fabric, namely afirst supply roll 110 containing a first nonwoven fabric 112 and asecond supply roll 114 containing a second nonwoven fabric 116. Thesupply station 102 also includes a plurality of supply spools eachcontaining an elastic strand, namely a first supply spool 118 containinga first elastic strand 120, a second supply spool 122 containing asecond elastic strand 124, a third supply spool 126 containing a thirdelastic strand 128, and a fourth supply spool 130 containing a fourthelastic strand 132. The elastic strands 120, 124, 128, 132 may have anysuitable cross-sectional shape that facilitates enabling the elasticstrands 120, 124, 128, 132 to function as described herein (e.g., across-sectional shape that is round, rectangular (e.g., relativelyflat), square, etc.).

The illustrated processing station 104 includes a rotary ultrasonicbonding apparatus (indicated generally by 200) for bonding the elasticstrands 120, 124, 128, 132 between the nonwoven fabrics 112, 116 to makean elastic nonwoven material 134, as set forth in more detail below. Thecollection station 106 may include any suitable device(s) for collectingthe elastic nonwoven material 134 (e.g., a puller roll 136). In otherembodiments, the supply station 102 may have any suitable quantity ofsupply rolls and supply spools having any suitable configuration thatfacilitates enabling the apparatus 200 to function as described herein.

FIGS. 2-7 are various embodiments of the rotary ultrasonic bondingapparatus 200. In the illustrated embodiments, the apparatus 200 has ananvil module 202 and a horn module 204 that cooperate to perform abonding operation of the elastic strands 120, 124, 128, 132 between thenonwoven fabrics 112, 116 as set forth in more detail below.

In the illustrated embodiments, the horn module 204 includes a frame 206on which are mounted a disc-like rotary horn 208, a motor 210 fordriving rotation of the horn 208 via a suitable drive train 212, and ahousing 214 which contains at least part of a vibration control unit(not shown) that causes the horn 208 to vibrate. The horn 208 has a face216 with a substantially continuous contour (i.e., the horn face 216 hasa contour that is substantially smooth (or uninterrupted) across itsentire surface area). In other embodiments, the horn face 216 may haveany suitable contour that facilitates enabling the horn 208 to functionas described herein.

In some embodiments, the vibration control unit (while not illustrated)includes at least one booster (e.g., a drive booster and an integralbooster) mechanically connected to a converter, which is electricallyconnectable to a generator. The converter is capable of converting highfrequency electrical energy supplied by the generator into mechanicalenergy (or vibration) that is selectively transmitted to the horn 208across the booster(s). The booster(s) are capable of modifying (i.e.,increasing or decreasing) the vibration transmitted to the horn 208 fromthe converter, such that the horn 208 (particularly, the face 216 of thehorn 208) vibrates while it rotates during a bonding operation, as setforth in more detail below. It is contemplated that the horn module 204may have any suitable operational components arranged in any suitablemanner that facilitates enabling the horn 208 to function as describedherein.

In the illustrated embodiments, the anvil module 202 includes a frame218 on which are mounted a disc-like rotary anvil 220 and a motor 222for driving rotation of the anvil 220 via a suitable drive train 224.The anvil 220 has an annular face 226, the contour of which is notcontinuous (i.e., is interrupted) as set forth in more detail below. Theanvil module 202 is positioned relative to the horn module 204 such thatthe anvil face 226 is rotatable in close proximity to the horn face 216,and vice versa, to facilitate ultrasonically bonding the elastic strands120, 124, 128, 132 between the nonwoven fabrics 112, 116 when theelastic strands 120, 124, 128, 132 are held in tension across apparatus200, as set forth in more detail below. As used herein, the term “closeproximity” refers to when the anvil face 226 is either in contact with,or is minimally spaced apart from, the horn face 216 when the horn 208is not ultrasonically vibrating.

In some embodiments, the apparatus 200 may be configured such that atleast one of the anvil module 202 and the horn module 204 isdisplaceable relative to the other via a suitable displacement mechanismoperable either: (A) when the system 100 is offline and the horn 208 isat rest (i.e., when the horn 208 is not rotating or vibrating); or (B)when the system 100 is online and the horn 208 is active (i.e., when thehorn 208 is rotating and vibrating).

With particular reference to the embodiment of FIG. 2, the apparatus 200may be configured as a continuous-nip apparatus in which the horn module204 is to be: (A) fixed in position relative to the anvil module 202when the system 100 is online and the horn 208 is active; and (B)displaceable relative to the anvil module 202 when the system 100 isoffline and the horn 208 is at rest. Such displacement is facilitated bya selectively actuatable pneumatic cylinder 228 (or other suitablelinear actuator) that connects the frames 206, 218 to one another. Inthis manner, the spacing between the horn face 216 and the anvil face226 is adjustable primarily for servicing the apparatus 200 when thesystem 100 is offline.

Referring now to the embodiment of FIGS. 3 and 4, the apparatus 200 mayalso be configured as an intermittent-nip apparatus in which the hornmodule 204 is displaceable relative to the anvil module 202 via a rotarycamming device 230 when the system 100 is online and the horn 208 isactive. The rotary camming device 230 has a follower 232 mounted to thehorn module frame 206, and a cam wheel 234 mounted to the anvil moduleframe 218 and rotatable via a servomotor 236. The cam wheel 234 has anirregular camming surface 238 such that, when the cam wheel 234 isrotated via the servomotor 236, the follower 232 rides along theirregular camming surface 238 to cyclically displace the horn moduleframe 206 relative to the anvil module frame 218 at a predeterminedfrequency. In this manner, the spacing between the horn face 216 and theanvil face 226, and/or the frequency at which the horn face 216 contactsthe anvil face 226, are selectively adjustable. Other displaceablearrangements of the horn module 204 and the anvil module 202 are alsocontemplated without departing from the scope of this invention.

As shown in the embodiment of FIGS. 5 and 6, the apparatus 200 may alsoinclude a pinching device 260. In the illustrated embodiment, thepinching device 260 includes a base 262 and a roller 264 floatinglymounted to the base 262 via at least one biasing element 266. Thepinching device 260 also includes a bracket assembly 265 by which thebase 262 and the roller 264 are mounted to at least one of the frame 206and the frame 218, such that the base 262 and the roller 264 areadjustable in at least two degrees of freedom (as set forth in moredetail below) in relation to the anvil 220 to facilitate use of thepinching device 260 in conjunction with anvils of different sizes.

The illustrated bracket assembly 265 includes a first bracket 267 and asecond bracket 268. The first bracket 267 has at least one linear slot269 through which a bolt 271 (which is fixed to either the frame 206 ofthe horn module 204 or the frame 218 of the anvil module 202) extends,and along which the bolt 271 is slidable, thereby rendering the firstbracket 267 translatable relative to the frame 206 and/or 218. Thesecond bracket 268 has at least one substantially arcuate slot 272through which a bolt 270 (which is fixed to the first bracket 267)extends, and along which the bolt 270 is slidable, thereby rendering thesecond bracket 268 rotatable relative to the first bracket 267. The base262 is mounted to the second bracket 268 such that the base 262 (and,therefore, the roller 264) are rotatably adjustable in a first degree offreedom via rotation of the second bracket 268, and are translatablyadjustable in a second degree of freedom via translation of the firstbracket 267.

The position of the base 262 and, therefore, the roller 264 are fixablevia the bolt 270 and the bolt 271 to achieve a desired pinching contactbetween the roller 264 and the anvil face 226. For example, in theillustrated embodiment, the base 262 and the roller 264 are orientedsuch that the biasing element 266 applies a biasing force orientedsubstantially perpendicular to a rotation axis of the anvil 220 whenviewed as in FIG. 6. In other embodiments, the pinching device 260 mayhave any suitable components arranged and movable (e.g., translatableand/or rotatable) in any suitable manner that facilitates enabling thepinching device 260 to perform the pinching action described herein(e.g., on any suitable bracket assembly that facilitates enabling thebase 262 and the roller 264 to be adjustable in at least two degrees offreedom such as, for example, two translating degrees of freedom, or onetranslating degree of freedom and one rotating degree of freedom).

In this manner, the pinching device 260 limits the snap-back potentialof elastic strands 120, 124, 128, 132 that become severed between horn208 and anvil 220 during a bonding operation. More specifically, thepinching device 260 effectively catches broken elastic strand(s) 120,124, 128, 132 between the roller 264 and the anvil 220 to prevent thebroken elastic strands 120, 124, 128, 132 from snapping back to theirrespective supply spool(s) 118, 122, 126, 130. Moreover, because theroller 264 rotates by virtue of being in contact with anvil 220, anybroken elastic strands 120, 124, 128, 132 are caught at the interface ofroller 264 and anvil 220 and are automatically fed back into theinterface between horn 208 and anvil 220. As such, the pinching device260 serves as a self-threading device for broken elastic strands 120,124, 128, 132.

Notably, the apparatus 200 may have any suitable quantity of anvilmodules 202 and/or horn modules 204 that cooperate with one another tofacilitate enabling the apparatus 200 to function as described herein.For example, as illustrated in the embodiment of FIG. 7, the apparatus200 may be configured with an anvil drum 274 in which a pair of anvils220 are positioned such that the drum 274 has a pair of predefined,annular faces 226 that are spaced apart from one another. In thismanner, the horn 208 of a separate horn module 204 is dedicated to eachsuch anvil face 226, thereby facilitating a bonding operation onconfined regions of larger nonwoven fabrics on which only partialelasticity is desired (e.g., segments of these larger nonwoven fabricson which elasticity is not desired may move along non-contact regions277 of the drum 274 to avoid interaction with the associated horn(s)208).

To facilitate minimizing the occurrence of elastic strands 120, 124,128, 132 being cut between the horn 208 and the anvil 220 during abonding operation, it is desirable to effectively hold the elasticstrands 120, 124, 128, 132 in place within notches of the anvil face 226while the nonwoven fabrics 112, 116 are bonded together between the horn208 and the anvil 220. At least the following operational parameterscontribute to minimizing the occurrence of elastic strands 120, 124,128, 132 being cut during a bonding operation: (A) the specific energysource (e.g., the amplitude of vibration of the horn 208 and itspressure when contacting the anvil 220); (B) the energy director (e.g.,the geometry of the anvil face 226); and (C) the material system (e.g.,the decitex and tension of the elastic strands 120, 124, 128, 132, andthe basis weight of the nonwoven fabrics 112, 116).

With respect to one such parameter (i.e., the geometry of the anvil face226), FIG. 8 is a laid-flat illustration of an embodiment of the anvilface 226 of the apparatus 200. In the illustrated embodiment, the anvilface 226 has a circumferential centerline axis 276 and a width dimension278 oriented perpendicular to the axis 276. The contour of the anvilface 226 is irregular (i.e., not continuous) along the axis 276, in thatthe anvil face 226 defines a plurality of circumferentially spacedridges 280. For example, in some embodiments, each adjacent pair ofridges 280 may have a spacing (or pitch) measured along the axis 276 ofbetween about 0.10 inches and about 1.00 inches (e.g., between about0.20 inches and about 0.50 inches). While all adjacent pairs of ridges280 on the anvil face 226 are substantially equally spaced apart fromone another in the illustrated embodiment, it is contemplated that thespacing between adjacent pairs of ridges 280 may vary along the axis 276in other embodiments.

In the illustrated embodiment, each ridge 280 extends substantiallylinearly across the circumferential axis 276 so as to span substantiallythe entire width 278 of the anvil face 226. Each ridge 280 has anextension axis 282 oriented oblique to the circumferential axis 276. Asillustrated in FIG. 9, each ridge 280 includes a plurality of lands 284spaced along its extension axis 282 such that each adjacent pair oflands 284 is spaced apart by (or flank) a notch 286. While the lands 284and notches 286 are illustrated on only a select few of the ridges 280in FIG. 8, it is understood that all ridges 280 of anvil face 226likewise have a set of lands 284 and notches 286 along their respectiveextension axes 282. Notably, adjacent ones of the lands 284 of eachridge 280 are shaped such that the corresponding notch 286 definedtherebetween is oriented substantially parallel to the circumferentialaxis 276 (i.e., the ridges 284 and the notches 286 each have alengthwise dimension 298 that is oriented substantially parallel to thecircumferential axis 276 in the illustrated embodiment).

In some embodiments, the anvil face 226 may be configured for acontinuous entrapment bonding operation. More specifically, in suchembodiments, each of the ridges 280 has at least one notch 286 that isaligned in the width dimension 278 with a corresponding notch 286 ofeach other ridge 280, and the lands 284 that flank each aligned notch286 are spaced to create widthwise adjacent bonds in the nonwovenfabrics 112, 116 that are close enough together in the width dimension278 to permanently hold the associated elastic strand 120, 124, 128, 132in tension therebetween. As a result, after the bonding operation iscomplete and the nonwoven fabrics 112, 116 are removed from the system100, at least one of the elastic strands 120, 124, 128, 132 issubsequently permitted to contract between circumferentially adjacentrows of bonds, but not between the widthwise adjacent bonds throughwhich the elastic strand(s) 120, 124, 128, 132 extend. The entrapmentbonding operation is therefore said to be continuous in the sense thatat least one of the elastic strands 120, 124, 128, 132 is caused to bepermanently held in tension between each widthwise adjacent pair ofbonds through which it extends.

In one embodiment of a continuous entrapment configuration of the anvilface 226, the lands 284 and the notches 286 of each ridge 280 have sizes(and, therefore, spacings) relative to one another that aresubstantially the same as those of all other ridges 280 on the anvilface 226. The notches 286 are generally U-shaped or generally V-shaped,such that the sidewalls of the lands 284 that flank each notch 286 may,when viewed from a cross-sectional profile of the notch 286 as shown inFIG. 9, form a wedge angle therebetween of about 0° (i.e., the sidewallsmay be about parallel to one another) and about 140° (e.g., betweenabout 60° and about 100°). Notches 286 of other shapes are alsocontemplated.

In one particular embodiment, if the elastic strands 120, 124, 128, 132have a decitex of between about 540.0 and about 1240.0, and if thenonwoven fabrics 112, 116 have a grammage (gsm) of between about 11.0and 16.0, the lands 284 may have lengths at their peaks of between about0.010 inches and about 0.25 inches (e.g., between about 0.030 inches andabout 0.060 inches), and widths at their peaks of between about 0.008inches and about 0.050 inches (e.g., between about 0.010 inches andabout 0.030 inches). Also, in that example, the notches 286 may have:depths measured from the peaks of their flanking lands 284 of betweenabout 0.005 inches and about 0.020 inches (e.g., between about 0.007inches and about 0.010 inches); widths measured at the peaks of theirflanking lands 284 of between about 0.006 inches and about 0.016 inches(e.g., between about 0.008 inches and about 0.012 inches); and widthsmeasured at their bases of between about 0.0025 inches and about 0.010inches (e.g., between about 0.003 inches and about 0.005 inches).

By providing the lands 284 and the notches 286 with the dimensions ofthe above example, the anvil face 226 facilitates improved gripping ofthe elastic strands 120, 124, 128, 132 in the notches 286 and,therefore, facilitates preventing the elastic strands 120, 124, 128, 132from withdrawing out of the notches 286 to reduce the occurrence ofsevered elastic strands 120, 124, 128, 132. Other suitable sizes for thelands 284 and the notches 286 are also contemplated without departingfrom the scope of this invention.

In other embodiments, the anvil face 226 may be configured for anintermittent entrapment bonding operation, such that the lands 284 thatflank at least one of the notches 286 are spaced to create widthwiseadjacent bonds in the nonwoven fabrics 112, 116 that are not closeenough together in the width dimension 278 to permanently hold theassociated elastic strand 120, 124, 128, 132 in tension therebetween. Asa result, after the bonding operation is complete and the nonwovenfabrics 112, 116 are removed from the system 100, the correspondingelastic strand 120, 124, 128, 132 is subsequently permitted to contractbetween the widthwise adjacent bonds through which it extends such thatits tension between those widthwise adjacent bonds is substantiallyrelieved. The entrapment bonding operation is therefore said to beintermittent in the sense that at least one of the elastic strands 120,124, 128, 132 is not permanently held in tension between all pairs ofwidthwise adjacent bonds through which it extends.

In one embodiment of an intermittent entrapment configuration of theanvil face 226, the anvil face 226 may be provided with a plurality ofdistinct circumferential regions 288 such that a dimension of a notch286 (and, therefore, the lands 284 that flank it) on a ridge 280 in atleast one circumferential region 288 is different than a dimension of awidthwise aligned notch 286 (and, therefore, the lands 284 that flankit) on a ridge 280 in at least one other circumferential region 288.

For example, each ridge 280 in a plurality of first circumferentialregions 290, 296 may have at least one notch 286 that is sizeddifferently as compared to at least one notch 286 that is widthwisealigned therewith on ridges 280 in a plurality of second circumferentialregions 292, 294 interspaced between the first circumferential regions290, 296. In this example, within the first circumferential regions 290,296, the notches 286 may be sized with larger widths (like in FIG. 9)such that the elastic strands 120, 124, 128, 132 do not later becomeentrapped across (i.e., are later permitted to slip between) thewidthwise adjacent bonds created at widthwise adjacent lands 284 onridges 280 in these first circumferential regions 290, 296. Whereas,within the second circumferential regions 292, 294, the notches 286 maybe sized with smaller widths (like in FIG. 10) such that the elasticstrands 120, 124, 128, 132 later become entrapped across (i.e., are notlater permitted to slip between) the widthwise adjacent bonds created atwidthwise adjacent lands 284 on ridges 280 in the second circumferentialregions 292, 294.

More specifically, in this example, at least one ridge 280 in eachsecond circumferential region 292, 294 may have its notches 286 sized inthe manner set forth above for the continuous entrapment example, whileat least one ridge 280 in each first circumferential region 290, 296 mayhave its notches 286 sized with a width (as measured at the peaks of itsflanking lands 284) of between about 0.010 inches and about 0.25 inches(e.g., between about 0.030 inches and about 0.060 inches in someembodiments; or about 0.035 inches in one particular embodiment). Thus,adequate slippage of the elastic strands 120, 124, 128, 132 across atleast one ridge 280 in each first circumferential region 290, 296 isfacilitated, especially when the elastic strands 120, 124, 128, 132 havea decitex of between about 540.0 and about 1240.0, and when the nonwovenfabrics 112, 116 have a grammage (gsm) of between about 11.0 and 16.0.

In both a continuous entrapment configuration and an intermittententrapment configuration, the anvil face 226 may have a plurality ofdistinct widthwise segments 281, wherein each widthwise segment 281 haslands 284 and/or notches 286 of comparatively different sizes. Forexample, in one particular embodiment illustrated by FIG. 11, the anvilface 226 may have a first widthwise segment 283 with lands 284 thatdefine notches 286 of a first width to suit elastic strands 120, 124,128, 132 of a first decitex, and a second widthwise segment 285 withlands 284 that define notches 286 of a second width that is less thanthe first width to suit elastic strands 120, 124, 128, 132 of a seconddecitex that is less than the first decitex. Thus, each widthwisesegment 281, no matter whether it is configured for continuous orintermittent entrapment, may be sized to accommodate elastic strands120, 124, 128, 132 of different sizes.

In yet other embodiments, the anvil face 226 may have ridges 280 thatextend non-linearly across the circumferential axis 276. For example, inone particular embodiment illustrated by FIGS. 12-14, the anvil face 226may define a plurality of ridges 280 each with a curvilinear axis (e.g.,a substantially arcuate axis 287). Notably, these embodiments withnon-linear ridges 280 may have the same dimensions for the lands 284 andthe notches 286 as for the substantially linearly extending ridges 280set forth above, including the same dimensional variations amongstcircumferential and widthwise regions 288, 281 as is set forth abovewith respect to the substantially linearly extending ridges 280.

FIG. 15 illustrates an elastic nonwoven material 300 fabricated usingthe system 100. In the illustrated embodiment, an intermittententrapment bonding process was performed on the nonwoven fabrics 112,116 (with elastic strands 120, 124 sandwiched therebetween) using one ofthe embodiments of the apparatus 200 set forth above. The embodiment ofthe anvil 220 utilized to fabricate the material 300 has an anvil face226 with notches 286 that vary in size across circumferential regions288 as set forth in some of the embodiments above. In this manner, withthe nonwoven fabrics 112, 116 and the elastic strands 120, 124 held intension across the apparatus 200, the horn face 216 and the anvil face226 created bonds 302 at locations corresponding to the lands 284 of theanvil face 226.

Once the bonded nonwoven fabrics 112, 116 (and the elastic strands 120,124 sandwiched therebetween) were subsequently removed from the system100, the tension in the elastic strands 120, 124 was partly relievedsuch that segments of each elastic strand 120, 124 were permitted tocontract to create material 300. More specifically, a first segment 304of each elastic strand 120, 124 became entrapped between adjacent rowsof bonds 302 that corresponded to the ridges 280 which defined notches286 of smaller widths. Whereas, a second segment 306 of each elasticstrand 120, 124 was permitted to slip across widthwise adjacent bonds302 in rows that corresponded to the ridges 280 which defined notches286 of larger widths. In this manner, the nonwoven fabrics 112, 116 werecaused to gather in areas 308 of the material 300 that have widthwiseadjacent bonds 302 of closer spacing (but not in areas 310 that havewidthwise adjacent bonds 302 of greater spacing) to effectively providethe material 300 with an elastic property. Notably, if a continuousentrapment operation had been utilized instead of an intermittententrapment operation, the material 300 would not have second segments306 that are permitted to slip, but would instead only have firstsegments 304 such that the nonwoven fabrics 112, 116 would gather alongthe entire material 300.

The rotary ultrasonic bonding systems and methods set forth herein areutilized to directly entrap tensioned elastic within a nonwoven fabricwithout the use of adhesives, thereby providing various functional andcommercial advantages. The systems and methods eliminate the complexadhesive delivery systems and costly adhesive materials associated withadhesive bonding processes, and the systems and methods provide asimpler, cleaner, and safer (e.g., cooler in temperature) productionenvironment, with lower power consumption and lower material costs.Also, various functional deficiencies of adhesively bonded materials areeliminated, including adhesive bleed-through, stiffening, and creep thatare common in conventional adhesively bonded materials. Thus, lower-costnonwoven/film substrates and elastic materials can be utilized.

Moreover, the systems and methods set forth herein facilitate a morecontinuous production sequence (i.e., increased process uptime) due, atleast in part, to the lack of: adhesive-related cleaning operations;adhesive system delivery/reliability issues; heated equipment cool-downperiods in advance of maintenance events; cold-start periods; andre-heat or purge-calibrate events. Additionally, a more continuousproduction sequence is further facilitated by the automatic threading(or self-threading) of severed elastic strands when the system isonline, as well as the use of continuously-running, over-the-end elasticspools.

Additionally, the systems and methods set forth herein are usable toattach (e.g., entrapment) elastic strands while also performing otherelastic processing steps such as cutting/chopping processes, seamingprocesses, edge trimming processes, etc. The systems and methods arefurther adaptable to existing capital asset bases to provide retrofitcapability (with customizable configurations if desired), as well asquicker grade-change capability as the attachment zone length changesvia a software interface.

The systems and methods also facilitate maximizing elastic performance.For example, the systems and methods facilitate lowering tension atelongation as compared to other attachment methods (e.g., the systemsand methods can provide a nearly pure elastic response for stress vs.strain when at least some substrates are utilized). The systems andmethods also facilitate minimizing creep (or loss of performance) (e.g.,the systems and methods produce elastic materials that are more robustin the face of temperature, time, and end-user solvents (e.g.,emollients)) due, at least in part, to the fact that the elastic strandscan be entrapped in a thermoplastic substrate, as opposed to beingattached to a substrate with a susceptible intermediate binder material.

The systems and methods further facilitate customized aesthetics andfunctional benefits. For example, gathers are produced by a bondingpattern and/or strand-feed positioning such that size, shape, andfrequency are selectable. Also, zoned tension is enabled, in thattension can be controlled by an elastic segment depending upon thedesired fabric configuration (e.g., depending upon the desiredcross-direction orientation within fabric (among lanes) and/orlongitudinal orientation within fabric (within lanes)). Curvedattachment is also facilitated if desired. Furthermore, controlledslip/creep for adjustable fit is facilitated, with intermittent orcontinuous attachment of elastic to the substrate being selectable toenable placement/zoning of live elastic and non-elasticized segments.

In addition to the embodiments of the systems and methods set forthabove, other embodiments are also contemplated. For example, non-rotarysystems of attachment (e.g., stationary (or blade) ultrasonic horns,heat, pressure, etc.) are contemplated. Also, in combination with therotary embodiments set forth above, adhesive systems may be usable inalternative embodiments. Moreover, latent elastics may be usable insteadof tensioned elastics in some embodiments. Then too, the systems andmethods facilitate curving (or shifting) elastic strands with lessoccurrence of breakage, and the systems and methods further facilitategenerating a matrix of tensions (e.g., a checkerboard effect),differential ruffling, dead zones, and/or simultaneous incorporation ofelastic strands of different decitex.

Notably, the systems and methods described herein facilitate fabricatinga variety of elastic nonwoven materials usable in a variety of articlessuch as personal care articles (e.g., adult briefs, baby diapers,child/adult pull-on pants, contour fit hygiene products, etc.) ormedical garments (e.g., masks, caps, gowns, footwear, etc.). Moreover,individual components (e.g., scrim/netting, diaper ears, discreetpanels, etc.) of an article can be fabricated using elastic nonwovenmaterials fabricated via the above-described systems and methods. Othercontemplated products in which the nonwoven materials can be utilizedinclude thermal insulation or filters (e.g., associated ruffling orblousing), as well as elastic-topped garbage bags, non-adhesivebandages, hair nets, house wrap, etc.

When introducing elements of the present invention or the preferredembodiment(s) thereof, the articles “a”, “an”, “the”, and “said” areintended to mean that there are one or more of the elements. The terms“comprising”, “including”, and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:
 1. An apparatus for fabricating an elastic nonwovenmaterial, said apparatus comprising: a rotary ultrasonic horn; and arotary anvil positionable in close proximity to the ultrasonic horn,wherein the anvil has a face with a width and a circumferential axis,the face having a plurality of ridges each of which defines a pluralityof interspaced lands and notches.
 2. The apparatus of claim 1, whereinthe ridges extend obliquely across the circumferential axis.
 3. Theapparatus of claim 1, wherein the ridges extend across substantially theentire width of the face.
 4. The apparatus of claim 1, wherein all pairsof adjacent ridges on the face are substantially equally spaced apartfrom one another along the circumferential axis.
 5. The apparatus ofclaim 1, wherein an adjacent pair of ridges has a spacing measured alongthe circumferential axis of between about 0.10 inches and about 1.00inches.
 6. The apparatus of claim 5, wherein the spacing is betweenabout 0.20 inches and about 0.50 inches.
 7. The apparatus of claim 1,wherein all of the notches on the face are substantially the same size.8. The apparatus of claim 1, wherein one of the notches is flanked by apair of the lands, each of the flanking lands having a peak such thatthe one notch has a width measured at the peaks of the flanking lands ofbetween about 0.006 inches and about 0.016 inches.
 9. The apparatus ofclaim 8, wherein the width is between about 0.008 inches and about 0.012inches.
 10. The apparatus of claim 1, wherein one of the notches isflanked by a pair of the lands, each of the flanking lands having a peaksuch that the one notch has a depth measured from the peaks of theflanking lands of between about 0.005 inches and about 0.020 inches. 11.The apparatus of claim 10, wherein the depth is between about 0.007inches and about 0.010 inches.
 12. The apparatus of claim 1, wherein oneof the notches is flanked by a pair of the lands, each of the flankinglands having a peak such that the one notch has a width measured at thepeaks of the flanking lands of between about 0.010 inches and about 0.25inches.
 13. The apparatus of claim 12, wherein the width is betweenabout 0.030 inches and about 0.060 inches.
 14. The apparatus of claim13, wherein the width is about 0.035 inches.
 15. The apparatus of claim1, wherein each of the lands has a peak, one of the lands having alength measured at its peak of between about 0.010 inches and about 0.25inches.
 16. The apparatus of claim 15, wherein the length is betweenabout 0.030 inches and about 0.060 inches.
 17. The apparatus of claim 1,wherein each of the lands has a peak, one of the lands having a widthmeasured at its peak of between about 0.008 inches and about 0.050inches.
 18. The apparatus of claim 17, wherein the width is betweenabout 0.010 inches and about 0.030 inches.
 19. The apparatus of claim 1,wherein the ultrasonic horn has a face with a contour that issubstantially continuous.
 20. The apparatus of claim 1, wherein the facehas a first circumferential region with ridges defining notches of afirst size, and a second circumferential region with ridges definingnotches of a second size different than the first size.
 21. Theapparatus of claim 20, wherein the face defines a spaced-apart pair ofthe first circumferential regions and a spaced-apart pair of the secondcircumferential regions.
 22. The apparatus of claim 1, wherein the facehas a first widthwise region in which the ridges define notches of afirst size, and a second widthwise region in which the ridges definingnotches of a second size different than the first size.
 23. Theapparatus of claim 1, wherein the ridges extend substantially linearlyacross the circumferential axis.
 24. The apparatus of claim 1, whereinthe ridges extend non-linearly across the circumferential axis.
 25. Theapparatus of claim 24, wherein the ridges extend substantially arcuatelyacross the circumferential axis.
 26. An apparatus for fabricating anelastic nonwoven material, said apparatus comprising: a horn moduleincluding a rotary ultrasonic horn mounted to a frame; an anvil moduleincluding a rotary anvil mounted to a frame and positionable in closeproximity to the ultrasonic horn; and a camming device displaceablyconnecting the horn module and the anvil module to cyclically displacethe horn module relative to the anvil module during a bonding operationof the apparatus.
 27. The apparatus of claim 26, wherein the cammingdevice includes a rotary cam wheel mounted to the frame of the anvilmodule.
 28. The apparatus of claim 27, further comprising a first motorto which the ultrasonic horn is rotatably connected, a second motor towhich the anvil is rotatably connected, and a servomotor to which thecam wheel is rotatably connected.
 29. An apparatus for fabricating anelastic nonwoven material, said apparatus comprising: a horn moduleincluding a rotary ultrasonic horn mounted to a frame; an anvil moduleincluding a rotary anvil mounted to a frame and positionable in closeproximity to the ultrasonic horn; and a pinching device mounted to oneof the frame of the horn module and the frame of the anvil module suchthat the pinching device is positionable to floatingly contact theanvil.
 30. The apparatus of claim 29, wherein the pinching deviceincludes a roller that floatingly contacts the anvil.
 31. The apparatusof claim 30, wherein the pinching device includes a base and a biasingelement by which the roller is floatingly mounted to the base.
 32. Theapparatus of claim 29, wherein the pinching device is adjustable in atleast two degrees of freedom.